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Electronic supplementary information

First Principles Study on Electrochemical and Chemical Stability of the Solid Electrolyte-

Electrode Interfaces in All-Solid-State Li-ion Batteries

Yizhou Zhu1, Xingfeng He1, Yifei Mo1,2*

1 Department of Materials Science and Engineering,

2 University of Maryland Energy Research Center,

University of Maryland, College Park, MD 20742

* Email: yfmo@umd.edu

Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A.This journal is © The Royal Society of Chemistry 2016

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Table S1. Calculated phase equilibiria for the LiPON solid electrolyte materials at applied

potential. (a) Li2.88PO3.73N0.14

Potential 𝜙 ref to Li/Li+(V)

𝜇!" ref to Li metal (eV)

∆𝑛!" per formula Phase equilibria

0.01 -0.01 8 Li3N, Li2O, Li3P 0.61 -0.61 7.72 Li7PN4, Li2O, Li3P 0.68 -0.68 7.44 LiPN2, Li2O, Li3P 0.69 -0.69 6.88 Li2PO2N, Li2O, Li3P

0 Li2.88PO3.73N0.14 1.07 -1.07 -0.01 Li2PO2N, LiN3, Li3PO4 1.67 -1.67 -0.01 Li2PO2N, N2, Li3PO4 2.60 -2.60 -0.42 N2, Li4P2O7, Li3PO4 3.58 -3.58 -0.80 N2, Li4P2O7, LiNO3 3.66 -3.66 -0.88 N2, Li4P2O7, NO2 3.71 -3.71 -0.98 Li4P2O7, LiPO3, NO2 3.77 -3.77 -1.12 Li4P2O7, LiPO3, LiNO3 4.33 -4.33 -1.74 LiPO3, O2, LiNO3 4.82 -4.82 -1.88 LiPO3, O2, N2O5 4.99 -4.99 -2.88 P2O5, O2, N2O5

(b) Li2.98PO3.3N0.46

Potential 𝜙 ref to Li/Li+(V)

𝜇!" ref to Li metal (eV)

∆𝑛!" per formula Phase equilibria

0.01 -0.01 8 Li3N, Li2O, Li3P 0.61 -0.61 7.08 Li7PN4, Li2O, Li3P 0.68 -0.68 6.16 LiPN2, Li2O, Li3P 0.69 -0.69 4.32 Li2PO2N, Li2O, Li3P

0 Li2.98PO3.3N0.46 1.07 -1.07 -0.29 Li2PO2N, LiN3, Li3PO4 1.67 -1.67 -0.33 Li2PO2N, N2, Li3PO4 2.60 -2.60 -0.98 Li2PO2N, N2, Li4P2O7 2.63 -2.63 -1.09 P3N5, N2, Li4P2O7 2.75 -2.75 -1.10 P4ON6, N2, Li4P2O7 2.77 -2.77 -1.38 LiPO3, N2, Li4P2O7 3.71 -3.71 -1.98 LiPO3, NO2, N2 4.38 -4.38 -2.98 P2O5, NO2, N2

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Table S2. Phase equilibria and decomposition energies of the SE-LCO and SE-L0.5CO interfaces.

a) LGPS

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO

0.06 CoO, Li3PO4, Li2SO4, Li4GeO4, Li6CoO4

-82 -83

0.159 Co, Li3PO4, Li2SO4, Li4GeO4, Li6CoO4 -210 -213 0.163 Co, Li2O, Li3PO4, Li2SO4, Li4GeO4 -213 -216 0.35 Co9S8, Li2O, Li3PO4, Li2SO4, Li4GeO4 -314 -321 0.42 Co9S8, Li2S, Li3PO4, Li2SO4, Li4GeO4 -340 -349 0.44 Co9S8, Li2S, Li2GeO3, Li3PO4, Li2SO4 -339 -348 0.52 Co9S8, Li2S, Li3PO4, Li2SO4, Li4GeS4 -329 -339 0.59 Co3S4, Li2S, Li3PO4, Li2SO4, Li4GeS4 -319 -331 0.61 CoS2, Co3S4, Li2S, Li3PO4, Li4GeS4 -313 -325

L0.5CO

0.0510 Co3O4, LCO, Li2GeO3, Li3PO4, Li2SO4 -230 -262

0.0513 Co3O4, LCO, Li2CoGeO4, Li3PO4, Li2SO4

-231 -263

0.088 CoO, LCO, Li2CoGeO4, Li3PO4, Li2SO4

-314 -346

0.090 CoO, LCO, Li3PO4, Li2SO4, Li4GeO4 -317 -349

0.10 CoO, Li3PO4, Li2SO4, Li4GeO4, Li6CoO4

-328 -360

0.13 Co, CoO, Li3PO4, Li2SO4, Li4GeO4 -360 -391 0.14 Co, CoO, Li2CoGeO4, Li3PO4, Li2SO4 -370 -401 0.31 Co, Co9S8, Li2CoGeO4, Li3PO4, Li2SO4 -467 -496 0.37 Co, Co9S8, Li3PO4, Li2SO4, Li4GeO4 -492 -520 0.397 Co9S8, Li2O, Li3PO4, Li2SO4, Li4GeO4 -498 -526 0.404 Co9S8, Li2S, Li3PO4, Li2SO4, Li4GeO4 -499 -527 0.43 Co9S8, Li2S, Li2GeO3, Li3PO4, Li2SO4 -492 -519 0.50 Co9S8, Li2S, Li3PO4, Li2SO4, Li4GeS4 -462 -489 0.59 Co3S4, Li2S, Li3PO4, Li2SO4, Li4GeS4 -428 -453 0.64 CoS2, Co3S4, Li2S, Li3PO4, Li4GeS4 -398 -423

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b) Li3PS4

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO

0.06 CoO, Li3PO4, Li2SO4, Li6CoO4 -90 -90 0.15 Co, Li3PO4, Li2SO4, Li6CoO4 -233 -233 0.16 Co, Li2O, Li3PO4, Li2SO4 -237 -237 0.34 Co9S8, Li2O, Li3PO4, Li2SO4 -368 -368 0.41 Co9S8, Li2S, Li3PO4, Li2SO4 -405 -405 0.48 Co3S4, Li2S, Li3PO4, Li2SO4 -405 -405 0.50 CoS2, Co3S4, Li2S, Li3PO4 -401 -401

L0.5CO

0.05 Co3O4, LCO, Li3PO4, Li2SO4 -238 -269 0.09 CoO, LCO, Li3PO4, Li2SO4 -331 -361 0.10 CoO, Li3PO4, Li2SO4, Li6CoO4 -344 -374 0.12 Co, CoO, Li3PO4, Li2SO4 -380 -409 0.36 Co, Co9S8, Li3PO4, Li2SO4 -552 -573 0.387 Co9S8, Li2O, Li3PO4, Li2SO4 -562 -582 0.394 Co9S8, Li2S, Li3PO4, Li2SO4 -564 -584 0.47 Co3S4, Li2S, Li3PO4, Li2SO4 -543 -560 0.53 CoS2, Co3S4, Li2S, Li3PO4 -518 -534

c) LiPON0.14

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO

0.93 CoN, Li3PO4, Li5CoO4 -35 -35 0.931 N2, CoN, Li3PO4, Li6CoO4 -35 -35 0.933 CoN, Li2O, Li3PO4 -35 -35 0.935 CoN, Co2N, LiN3, Li3PO4 -34 -34 0.96 Co2N, LiN3, Li2PO2N, Li3PO4 -21 -21 0.98 Co, LiN3, Li2PO2N, Li3PO4 -11 -11

L0.5CO

0.59 Co3O4, LCO, LiNO3, Li3PO4 -65 -79 0.80 N2, Co3O4, LCO, Li3PO4 -62 -69 0.88 N2, CoO, LCO, Li3PO4 -56 -60 0.90 N2, CoN, CoO, Li3PO4 -53 -56 0.94 N2, CoN, Li3PO4, LiCoPO4 -42 -44 0.95 N2, CoN, Li3PO4, Li4P2O7 -38 -40 0.987 N2, CoN, Li2PO2N, Li3PO4 -12 -12 0.988 CoN, LiN3, Li2PO2N, Li3PO4 -11 -11 0.991 Co2N, LiN3, Li2PO2N, Li3PO4 -8 -8 0.993 Co, LiN3, Li2PO2N, Li3PO4 -7 -7

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d) LiPON0.46

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO

0.77 CoN, Li3PO4, Li5CoO4 -96 -96 0.79 N2, CoN, Li3PO4, Li6CoO4 -98 -98 0.81 CoN, Li2O, Li3PO4 -99 -99 0.82 Co2N, LiN3, Li2O, Li3PO4 -95 -95 0.83 Co, LiN3, Li2O, Li3PO4 -91 -91

L0.5CO

0.30 Co3O4, LCO, LiNO3, Li3PO4 -117 -140 0.52 N2, Co3O4, LCO, Li3PO4 -148 -164 0.62 N2, CoO, LCO, Li3PO4 -154 -167 0.77 N2, CoN, LCO, Li3PO4 -144 -152 0.838 N2, CoN, Li3PO4, Li5CoO4 -138 -143 0.843 N2, CoN, Li3PO4, Li6CoO4 -138 -143 0.849 N2, CoN, Li2O, Li3PO4 -136 -141 0.851 CoN, LiN3, Li2O, Li3PO4 -136 -141 0.857 Co2N, LiN3, Li2O, Li3PO4 -131 -136 0.863 Co, LiN3, Li2O, Li3PO4 -126 -131

e) LLZO

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO 0.96 La2O3, Li6Zr2O7, Li5CoO4 -1 -8

L0.5CO

0.47 O2, La2Zr2O7, La2O3, Li7Co5O12 -39 -60 0.49 La2Zr2O7, La2O3, Li2O2, Li7Co5O12 -38 -58 0.87 La2O3, Li2O2, Li7Co5O12, Li6Zr2O7 -14 -24 0.93 La2O3, Li7Co5O12, Li6Zr2O7, Li8CoO6 -8 -17 0.98 La2O3, Li6Zr2O7, Li8CoO6, Li5CoO4 -3 -11

f) LLTO

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO 0.64 Co3O4, La2Ti2O7, Li2TiO3, L0.5CO -0.5 -44 0.98 Co3O4, La2Ti2O7, L0.5CO, Li4Ti5O12 -0.04 -67

L0.5CO - LLTO, L0.5CO (stable) 0 -

g) LATP

𝐶!"#$%&'(# x Phase equilibria Δ𝐸!,!"#"$% (meV/atom)

Δ𝐸!,!"!#$ (meV/atom)

LCO

0.25 Co3O4, LiAl5O8, Li3PO4, L0.5CO, Li2TiO3 -41 -48 0.29 Co3O4, LiAl5O8, Li3PO4, L0.5CO, Li4Ti5O12 -48 -56 0.32 Co3O4, TiO2, LiAl5O8, Li3PO4, L0.5CO -53 -62 0.35 Co3O4, AlPO4, TiO2, Li3PO4, L0.5CO -53 -63 0.52 Co3O4, AlPO4, LiTiPO5, Li3PO4, L0.5CO -41 -56

L0.5CO - LATP, L0.5CO (stable) 0 -

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Table S3. Phase equilibria and decomposition energies for the SE-LCO interfaces under applied potential.

Interface Applied voltage ϕ

(V) Phase equilibria under ϕ

and at x = xm(ϕ) Δ𝐸!,!"#,!"#"$%

!"#$ (meV/atom)

Δ𝐸!,!"#,!"!#$!"#$

(meV/atom)

LGPS-LCO

2.00 – 2.14 Co9S8, Li2SO4, Li3PO4, Li2GeO3 [-540, -519] [-546, -525] 2.14 – 2.45 Co3S4, Li2SO4, Li3PO4, Li2GeO3, [-556, -543] [-604, -551] 2.45 – 2.62 Co3S4, Li2SO4, Li3PO4, Li2Ge7O15 [-547, -542] [-645, -611] 2.62 – 2.90 Co9S8, Li2SO4, Li3PO4, GeO2 [-542, -536] [-683, -632] 2.90 – 3.00 Co9S8, Li2SO4, LiCoPO4, GeO2 [-541, -536] [-696, -675] 3.00 – 3.14 Co3S4, Li2SO4, LiCoPO4, GeO2 [-551, -542] [-764, -728] 3.14 – 3.20 Co3S4, Li2SO4, Co3(PO4)2, GeO2 [-557, -552] [-773, -759] 3.20 – 3.32 Co3S4, CoSO4, Co3(PO4)2, GeO2 [-583, -559] [-787, -744] 3.32 – 5.00 Co9S8, CoSO4, Co3(PO4)2, GeO2 [-696, -588] [-1269, -767]

LLTO-LCO

2.00 – 2.58 Li2TiO3, La2TiO5, CoO [-73, -21] [-130, -71] 2.58 – 2.63 Li2TiO3, La2TiO5, Co3O4 [-19, -18] [-63, -62] 2.63 – 3.34 Li2TiO3, La2Ti2O7, Co3O4 [-17, -1] [-71, -54] 3.34 – 3.71 LLTO, L0.5CO 0 [-152, -68] 3.71 – 4.10 La2Ti2O7, TiO2, O2, L0.5CO 0 [-68, -9] 4.10 – 5.00 La2Ti2O7, TiO2, O2, CoO2 0 [-113, -9]

LATP-LCO

2.00 – 2.27 Li3PO4, LiAlO2, Li2TiO3, Co [-282, -223] [-326, -242] 2.27 – 2.37 Li3PO4, Al2CoO4, Li2Ti3CoO8, Co [-213, -193] [-233, -213] 2.37 – 2.53 Li3PO4, Al2CoO4, Li2Ti3CoO8, CoO [-189, -168] [-205, -184] 2.53 – 2.88 Li3PO4, Al2CoO4, TiCoO3, CoO [-165, -121] [-182, -138] 2.88 – 3.14 Li3PO4, Al2CoO4, Ti2CoO4, Co3O4 [-118, -101] [-133, -116] 3.14 – 3.40 Li3PO4, Al2CoO4, TiO2, Co3O4 [-99, -81] [-116, -101] 3.40 – 3.59 Li3PO4, LiAl5O8, TiO2, Co3O4 [-78, -54] [-109, -85] 3.59 – 3.94 Li3PO4, AlPO4, TiO2, Co3O4 [-51, -8] [-82, -38] 3.94 – 4.00 Li3PO4, AlPO4, LiTiPO5, Co3O4 [-5, -2] [-35, -32] 4.00 – 4.10 LATP, L0.5CO 0 [-32, -32] 4.10 – 4.22 LATP, CoO2 0 [-47, -32] 4.22 – 4.53 Li3PO4, AlPO4, LiTi2(PO4)3, O2 [-2, 0] [-38, -30] 4.53 – 5.00 LATP, L0.5CO 0 [-113, 52]

LiPON0.46-LCO

2.00 - 2.33 N2, CoN, Li3PO4 [-124, -124] [-191, -173] 2.33 - 2.87 N2, CoO, Li3PO4 [-137, -118] [-233, -182] 2.87 - 3.20 N2, Co3O4, Li3PO4 [-116, -103] [-260, -220] 3.20 - 3.43 LiNO3, Co3O4, Li3PO4 [-114, -103] [-245, -193] 3.43 - 3.57 LiNO3, LiCoPO4, Li3PO4 [-123, -112] [-359, -327] 3.57 - 3.72 LiNO3, LiCoPO4, Co3O4 [-137, -126] [-392, -359] 3.72 - 4.18 LiNO3, LiCoPO4, Co3(PO4)2 [-145, -137] [-523, -404] 4.18 - 4.23 LiNO3, CoPO4, Co3(PO4)2 [-148, -146] [-540, -529] 4.23 - 4.48 LiNO3, CoPO4, Co(NO3)2 [-160, -149] [-639, -548] 4.48 - 4.54 LiNO3, CoPO4, Co(NO3)4 [-154, -153] [-663, -647] 4.54 - 4.60 LiCo(PO3)4, CoPO4, Co(NO3)4 [-152, -152] [-715, -697] 4.60 - 5.00 Co(PO3)3, CoPO4, Co(NO3)4 [-152, -152] [-918, -739]

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Table S4. The phase equilibria and decomposition energies of the coating layer interfaces with Li3PS4 or LLZO.

𝐶!" 𝐶!"#$%&' xm Phase equilibria at minimum interfacial reaction energy

Δ𝐸!,!"#,!"#"$% (meV/atom)

Δ𝐸!,!"#,!"!#$(meV/atom)

Li3PS4 Li4Ti5O12 0.53 TiS2, Li3PO4, Li4TiS4 -80 -80 LiNbO3 0.54 S, Li2S, Li3PO4, Li5/7NbS2 -155 -155 LiTaO3 0.54 S, Li2S, Li3PO4, Li4/3Ta2S4 -49 -49 Li2SiO3 0.25 Li2S, Li3PO4, SiO2 -19 -19 Li3PO4 / Li3PS4, Li3PO4 0 0

LLZO

Li4Ti5O12 0.46 La2Zr2O7, La2TiO5, Li2TiO3 -75 -78 LiNbO3 0.62 LaNbO4, La2Zr2O7, Li3NbO4 -76 -79 LiTaO3 0.54 La3NbO7, La2Zr2O7, Li3TaO4 -68 -72 Li2SiO3 0.53 La2Zr2O7, La2O3, Li4SiO4 -29 -32 Li3PO4 / LLZO, Li3PO4 0 -

Figure S1. Calculated Δ𝐸!,!"#"$% of a) Li3PS4-coating layer interfaces and b) LLZO-coating layer interfaces

a)

b)